test: support writing test output to file

This is a minimal effort to support test output written both to
stdout and file in order to get our buildbots understanding
test output.

Cherry picked from jbergstroem/node@3194073
Original commit message follows:
  PR-URL: nodejs/node#934
  Reviewed-By: Chris Dickinson <[email protected]>
  Reviewed-By: Ben Noordhuis <[email protected]>

Conflicts:
	tools/test.py

Conflicts:
	tools/test.py

tools/test.py

@@ -29,6 +29,7 @@
 
 
 import imp
+import logging
 import optparse
 import os
 import platform
@@ -45,6 +46,8 @@
 from Queue import Queue, Empty
 import utils
 
+logger = logging.getLogger('testrunner')
+
 VERBOSE = False
 
 
@@ -225,7 +228,7 @@ def HasRun(self, output):
 class TapProgressIndicator(SimpleProgressIndicator):
 
   def Starting(self):
-    print '1..%i' % len(self.cases)
+    logger.info('1..%i' % len(self.cases))
     self._done = 0
 
   def AboutToRun(self, case):
@@ -238,26 +241,26 @@ def HasRun(self, output):
       status_line = 'not ok %i - %s' % (self._done, command)
       if FLAKY in output.test.outcomes and self.flaky_tests_mode == "dontcare":
         status_line = status_line + " # TODO : Fix flaky test"
-      print status_line
+      logger.info(status_line)
       for l in output.output.stderr.splitlines():
-        print '#' + l
+        logger.info('#' + l)
       for l in output.output.stdout.splitlines():
-        print '#' + l
+        logger.info('#' + l)
     else:
       status_line = 'ok %i - %s' % (self._done, command)
       if FLAKY in output.test.outcomes:
         status_line = status_line + " # TODO : Fix flaky test"
-      print status_line
+      logger.info(status_line)
 
     duration = output.test.duration
 
     # total_seconds() was added in 2.7
     total_seconds = (duration.microseconds +
       (duration.seconds + duration.days * 24 * 3600) * 10**6) / 10**6
 
-    print '  ---'
-    print '  duration_ms: %d.%d' % (total_seconds, duration.microseconds / 1000)
-    print '  ...'
+    logger.info('  ---')
+    logger.info('  duration_ms: %d.%d' % (total_seconds, duration.microseconds / 1000))
+    logger.info('  ...')
 
   def Done(self):
     pass
@@ -1192,6 +1195,8 @@ def BuildOptions():
       default='release')
   result.add_option("-v", "--verbose", help="Verbose output",
       default=False, action="store_true")
+  result.add_option('--logfile', dest='logfile',
+      help='write test output to file. NOTE: this only applies the tap progress indicator')
   result.add_option("-S", dest="scons_flags", help="Flag to pass through to scons",
       default=[], action="append")
   result.add_option("-p", "--progress",
@@ -1361,6 +1366,13 @@ def Main():
     parser.print_help()
     return 1
 
+  ch = logging.StreamHandler(sys.stdout)
+  logger.addHandler(ch)
+  logger.setLevel('INFO')
+  if options.logfile:
+    fh = logging.FileHandler(options.logfile)
+    logger.addHandler(fh)
+
   workspace = abspath(join(dirname(sys.argv[0]), '..'))
   suites = GetSuites(join(workspace, 'test'))
   repositories = [TestRepository(join(workspace, 'test', name)) for name in suites]